Control device for gaseous fuel burners



April 8, 1952 H. w. RICE CONTROL DEVICE FOR GASEOUS FUEL BURNERS 2 SHEETS-SHEET 1 Filed May 18, 1946 INVENTOR.

HAROLD W. RICE BY Wy ATTORNEY.

April 8, 1952 H. w. RICE CONTROL DEVICE FORGASEOUS FUEL BURNERS 2 SHEETS-SHEET 2 Filed May 18, 1946 INVENTOR. HAROLD W. RKJE ATTORNEY.

bine d safety-and timing control;

Patented Apr. 8, 1952 CONTROL D EVICE FOR GASEOUS FUEL BURNERS Harold W. Rice, Angeles, Calif., assignor to Robertshaw-Fulton Controls Company, a corporation of Delaware Application Mayi 18, 1946, Serial No. 670,756

' claim. (01. 137-439) This invention relates to control devices for gaseous fuel burners and, more particularly; to combined safety and timing controls. N *1 Domestic gas cooking ranges may havjejthe -main or oven burner controlled by automatic timin'gmeans such as an electric clock jtiiner so that the flow of fuel is automaticall'yjfshut off at'the end of a cooking period. The'jshutofi element may also be under the controlfbf' a safety device which operates independentlyof the timing device to prevent the, flow offuel to the main burnerwhenever an associated pilot burner is not burning. The safetydev e is usually of the thermomagnetic type and requires resetting to a fully operative positi'oneachtime the flow of fuel to the main burner by a single shut-off element which is responsive to both a timing means and a thermomagnetic safety device.

Another object of the invention is to render the shut-off element normally responsiveto the safety device even if the timing means is no longeroperative.

Another object of the invention is to. afford easy access to those parts of the control requiring manual operation. 1

Another object of the invention is to visually indicate the operative or inoperative condition of the safety device. I

Other objects and advantages will become apparent from the following description taken in connection with the accompanying drawings wherein:

) Fig. 1 is a front elevation partly in longitudinal section of the combined safety andtimin'g con trol. and showing the timing means in broken lines;

Fig. 2 is a section taken on the line I 1 Fig; 1; 3-:

' "Fig. 3 isa top plan view with'the cover broken away-to show the'inside'st'ructure of the cam 4 is a section taken on of Fig. 3;and h I V IFig.5,is a section taken on the line V-V of Fig. 1.

the line IV-IV Referring to the drawings, the control device 7 comprises generally a control means-l0, a-positioning means I2 and a holding means l4, all

after. In the arrangement shown, the axes of the control means III, the holding means [4 and the positioning means [2 are substantially parallel and the control and holding means are arranged in substantially the same horizontal plane with the positioning means I2 in intermediate overlying relationship. As indicated in Fig- ;.3. the -control device as a unit is conveniently se-. cured by any suitable means (not shown) upon the back-guard of a domestic gas range where it normally will be hidden from sight of the range use'r. As indicated schematically in Fig. 1, the gasrange is supplied with fuel from a main fuel pipe 18 towhich a conduit 20 is connected for supplying fuel to a pilot burner 22. The pilot burner '22 is located in lighting proximity to a 'main burner 24 which is connected to the'control means H) by a fuel pipe 26. i

The control means I!) comprises a generally rectangular hollow body 28 having an inletopening "38 and an outlet opening 32 in the underside thereof and'being suitably threaded or otherwise formed for connection with the fuel pipes 18 and 26, respectively; A'partition is formed integrally within the body 28 and serves to sepa rate .the inlet opening 38 from the outlet opening 32. 'Passage of fuel between these openings is provided for by the provision ofan opening 38 extending through the partition 34 axially' of the valve body 28 andbeing provided on one side of its peripheral wall with a valve seat 38. LA valve member 40 is cooperable with the. valve seat 38 to control flow of fluid through the opening 36 and is normallybiased to closedposition-by a coil spring 42 operative between the valve member 40 and a closure cap 44 threadedly secured in an opening 45 formed in the body. 28 between-the inlet and outlet openings.

A valve stem 46 is secured to the valve member 40 on the side opposite the coil spring 42 and extends through the opening 36 into slidable engagement with a stem bushing 48 whichuis threadedly secured to the body 28 opposite the cap 44. The bushing 48 may be assembled in the body 28 by insertion through the threaded opening 45" and the valve seat opening- 36 before the cap 44 is positioned. The valve stem. 46 extends through the bushing 48 into abutting engagement with a sealing diaphragm .50 which is similarly engaged on the opposite side by :an operating stem 52 axially aligned with the valve stem 46 and extending exteriorly of the body l8. It is apparent that pressure applied to the projectingend of the operating stem 52 willbe transmitted to the valve stem 46 through the diaphragm and will serve to overcomerthe bias of spring 42 to disengage the valve member 40 from its seat 38. I 1 "I'h e holding means is of the thermomagnetic of which will be described more fully hereintypeandcomprises a magnet housing 54 within which a horseshoemagnet 56 is rigidly mounted. An armature member 58 is adapted tobe moved into attracted position with the pole faces of the magnet 56 against the bias of a coil spring 66.

The coil spring 66 is operative between an outer end face of the magnet housing 54 and an end face of an extension 62 of an armature stem 64 which projects from the housing 54. The armature stem extension 62 is rigidly secured to the armature stem 64 and is provided with an annular groove 66 and a reduced axial portion 68 wh ch portion is adapted for slidable engagement with an axial opening I6 formed in one end of a thrust button I2. It may be noted here that the bore 16 is-formed somewhat deeper than the entire length of the reduced portion 68 for a purpose to be described hereinafter.

Both the control device I6 and the holding means I4 are mounted upon the underside of a rectangular platform 14 which may be utilized to securethe control device as a unit to the backguardof the range. In the case of the control means I6 the securing means takes the form of a pair of screws I6 each provided with a collar 'lB which serves to space the controlbody 28 from the platform I4. In the case of the holding means I4 an angular frame 86 (shown more clearly n Fig. 4) is employed and is provided with a pair of ears 82 at one end with which a pair of screws 84 cooperate to secure the frame 86 to the underside of the platform l4. The frame 86 has a portion extending substantially normal to that portion having the ears 82 and abase portion 86 extending substantially parallel to the latter portion. The magnet housing 54 1 mounted on the base portion 86 and is secured thereto by means of a-nut 88 which engages with a threaded extension of the magnet housing 54. I

Preferably, a casing 96 of sheet material en closes the holding means I4 and extends between the control body ZBand the platform I4. Hence, the casing 96 may conveniently be supported at one end'between the collars 'Iaassociatedwith the control body 28 and at the other end by a-lock-nut 92 which engages the threaded extension of the magent housing 54 on the opposite side of the casing 96 to the nut 88;

.The holding means I4 is responsive to a controlling condition and, in this embodiment, is responsive to the presence or absence of a flameat the pilot burner 22. Thus, a winding 94 provided for the magnet 56 and is adapted to be energized by current generated by a thermocouple 96. As shown schematically in Fig. 1, the thermocouple 96 is electrically connected at one end with the winding 94 and has its hot junction exposed 4 abuts against the underside of the platform I4. Manual pressure applied to the push-button 98 is transmitted to the thrust button I2 by a bell- .crank lever I I4 having one leg projecting through an aperture H6 in the slide bar I66 and another leg projecting through a slot II! in the adjacent upturned flange I64 and terminating in a rounded end H8 for operative engagement with the head II6 of the thrust button I2. The lever H4 is adapted for pivotal movement on the support plate I66 by the provision of oppositely disposed lugs I26 formed at the junction of the two legs of the lever H4 and loosely mounted Within oppositely disposed arcuate bearing portions I22 formed on the adjacent'end of the support plate The positioning means I2 takes the form of a push rod I24 conveniently formed in three parts for ease of assembly. One part comprises a headed stem I26 having an axial aperture'therea for sliclable movement within a bushing I36 which to the flame of the pilot burner 22. The current now so generated is sufficient to retain the armature 58 in attracted position relative to the pole faces of the magnet 56 but is insufiicient to actuate the armature 58 to this position. Consequently, manual resetting means, now to bedescribed, are employed to place the armature 58 in attracted position and render the holdingmeans effective.

The resetting means, as shown most clearly in Fig. 4, comprises apush-button 96 which is secured on one end of a slide bar I66 which extends through aligned'apertures I62 formed in upis secured by welding or other suitable method in an aperture in the platform I4 positioned intermediate the control means I6 and the holding means I4. The headed stem'I28 projects on the underside of the platform I4, whereas the headed stem I26 projects on the opposite side thereof and is spaced from the end face of the bushing I36 to permit reciprocable movement of the push rod I24. An indicated in broken lines in Fig. 1 of the drawing the push rod I24 is adapted for operative engagement with the operating stem (not shown) of an electric clock I32 which is shown positioned on the platform I4 surmounting the control means I6 and the holding means I4. The clock I32 forms a timing or other condition controlling means for governing the length of the cooking operation, as will be hereinafter apparent and may be detachably secured to the platform I4 by engagement with snap buttons I34 yieldably mountedon the platform I4.

This invention is more particularly directed toward means for operatingthe valve member 46 to control flow of fuelto the main burner 24 for the period set by the clock, or other condition controlling means, and for causing the valve to close to shut off the fuel supply to the main burner 24 in the event that the pilotburner 22 becomes extinguished. To this end, a lever device designated generally at I 36 is provided for transmitting movement of the push rod I24 to the valvemember 46 and also for transmitting movement of themanual push button 98 to theholding means I4.

Thelever device I36 takes the formv of a pair of lever arms I38 and I46 positioned for pivotal movement within the casing 96. The lever arm I38 is pivoted intermediate its ends on the lever arm I46 and extends from the axis of the control means I6 to beyond the axis of the holding. means I4. Thus, a pair of depending ears I42 are provided on the lever arm I38 and bear against the sides of the lever arm I46which is of channelshaped form. A pin I44 extends through the ears I42 and the sides of the lever arm I 46,to form the pivot point or fulcrum of the lever arm I36. The motion of the lever arm I38 is transmitted to the stem 52, which projects from the control body 28, by means of an adjusting screw I46 which extends perpendicularly from the lever arm I38 into engagement with the end of the stem 52.

The opposite end of the lever arm I38 beyond the holding means I4 is engaged by a coil spring I48 which is operative between the lever arm I38 and a stationary angular arm I50 projecting from the frame-86. The coil spring I48 tends, to rotate the lever arm I38 in a counter-clockwise direction on the'pivot I44'and overcomes the bias of the coil spring 42 while maintaining engagement between the lever arm I38 and the headed stem I28 of the push rod I24 of the timingmechanism. The lever arm I38 is further provided with an aperture through which the thrust button I2 extends and the sides of the lever arm adjacent the aperture'are suitably crimped to provide a raised bearing surface I52 for engagement with the shoulder II2 on the thrust button I2.

As previously stated, the other lever arm I40 is of channel form and is mounted for pivotal movement on a pin I55 carried by a relatively stationary support I54 through which it'extends substantially parallel with the pivot pin I44 for the-lever I38. The support I54 depends from the underside of the platform I4 to which it is secured bya screw I56. The lever arm I 40 is provided-with an extension I58 beyond the channel-shaped portion which terminates in a notched end for operative engagement with the recessed portion 66-of the magnet stem extension 62. Thus, up'onreciprocation of the stem extension '62 the lever arm I40 willbe rotated on its pivot In order that visual indication of the condition of the thermomagnetic means may be provided ascrew I66 projecting from the platform I4 and having itsopposite end provided with-an arcuate plate I68 carrying the indicia on and off. A pair of stop pins. I'I0 project from the platform 14- and are spaced one from the other on either side of the indicator arm I64 to limit pivotal movement thereof in two positions for displaying either of the indicia through a window I I2 formed in the front casing of the clock I 32.

A second casing N4 of sheet material is provided' to enclose the indicating mechanism and the resettingmeans. This casing II4 has crimped projecting ends II5 which extend through suitable apertures in the platform I4 and serve as resilient locking means to detachably retain the casing in position. An aperture H6 is provided in the top of the casing I'I4 through which the push-rod I 24 may project and, similarly, apertures I11; and I19 are provided in the front thereof through which the push-button 98 may project I and the indicia on the arcuate plate I68 may be ;vi ewed through the window I I2 respectively. The front casing of the clock I32 is additionally apertured to permit the push-button 98 to project therethrough as indicated in Fig. 3.

In the operation of the device, the condition controlling means such as the electric clock I32 may terminate the cooking period by closing the valve 40 which is shown in the open positionwith both burners 22 and 24 inoperation. In this valve closing operation, the push-rod I24 is forced downwardly by the clock actuator (not shown) so that the threaded stem I28 which is engaged with the lever arm I38 causes this lever arm to pivotabout the pin I 44. Thus, a clockwise movement of the lever arm I38, asviewed in Fig. ,1, occurs causing the adjusting screw. I46 to be raised allowing the valve spring 42 to close the valve 40. On the other hand, when the clock operates to open thevalve 40. the downward force on-the push-rod I24:is 1 removed. The coil spring I 48-then rotates the lever arm I38 counter-clockwise and causes movement of the valve 40 from its seat 38 against the'lbias of the valve spring 42. In-the event that -the flame from the pilot burner 22 is extinguished, then the thermocouple 96 ceases to generate-sufficient current to maintain the armature 58- in attracted position relative to the pole faces of the magnet 56. The stem extension 62 is movedf 'upwardly as viewedin Fig. 1,,,by the bias of the coil spring 60 so that-the shoulder thereon engages the underside of the thrust button I2. The -extension I 58 of the lever arm I40, which engages the recessed portion 66, is thus rotated counterclockwise on its pivot I55 causing the-other pivot pin I44 to be raised. As the lever arm I38 is "attached to the pin I44 it is caused to rotateabout the headed stem I28 as a fulcrum and to lift the adjusting screw I46 whereupon the valve 40 {is closed under bias of the spring 42. It' is apparent, however, that ifthe push-rod I 24 is being forced to its' downward position by the clock-actuator at the time that the magnet'56 releases'the armature 58, then the valve 40 is initially closed. The lever ar'm I40 nevertheless rotates asdescribed and causes the lever arm I38 to move-still farther. Thus, if the clock actuator releases pressure on the push-rod I 24 the valve 40 cannot open.

During the period that the pilot flame is'burning and the holdingmeans I4 is eifective, indicia On appears in the window I12. This is due to the lever arm I40" being held downwardly and causing the upturned portion I60 thereof to operate the indicator arm'I64 to the right, as viewed in Figs. 1 and 3, thus 'positioning the plate I 68 against the right-hand'stop pin I'I0. However, when the pilot fiame extinguished and the lever arm extension-I58 moves counter-clockwise as described, then thef'upturned portion I60 of" lever'arm I40 moves to the left and reverses the position of th plate I68 through the linkage described. The indicia .ofi then appearsin the window indicating to the operator that the pilot burner need-s relighting. The indicia "on does not, of course. changef'during a normal cooking operation when the clock actuator operates the lever arm I38 only andcauses opening and closing of the valve 40 to control the main burner 24.

It is only when the magnet 56 releases and openates lever arm I40 that the indicia is changed from on to ofi indicating that the holding means is no longer effective.

After the describeds'afety operation due to extinguishment of the pilot burner 22, the device must be reset before another cooking operation can be conducted. The pilot burner is first relighted and,. after a short waiting period, the thermocouple heats su'fliciently to generate current for holding theparmature 58 in attracted position. The push-mittens is then manually operated to cause the bell crank I I4 to force the thrust button I2 downwardly as viewed in Fig. 1, or to the left as viewed in Fig. 4. Since the extension stem 62 is initially in abutting relation withthe end face of the thrust button I2, then the lever. arm extension I58 is moved clockwise due to its engagement with the recessed portion 66. After a relatively short movement in this direction, the collar II2 on the thrust ,button a alsro w contacts'the bearing surface I52 on th lever arm I38, provided that the push rod I24 is in its retracted position and is not being forced downwardly; by the clock actuator. In the retracted push rod position, the leverarm I38 is moved in a clockwise direction, causing both th coil springs I48 and B to be compressed. During this resetting operation the other lever arm I40 is also: rotated clockwise so that both lever arms I38 and I40 are rotated about the pivot pin I55. Thearmature is thus reset in attracted position relative to the pole faces of the magnet 56 and is retained in suchposition until the pilot burner 22 is again extinguished. It will be apparent from the previously described action that the indicia on appears in the window I12 when the resettingoperation is completed. ,Itshould be noted that the simple and economical lever device renders it impossible to open the valve 40 during the resetting operation or at any time that the magnet is not energized and holding the armature in attracted position. Thus, main burner fuel cannot be admitted to the burner compartment before the pilot burner is lighted. There is no danger of explosion when a lighted match is inserted in this compartment forthe purpos of igniting the pilot burner.

When the pushbutton 98 is released after the resetting operation is completed as described, the extension stem'62 and the lever arm I40 are held in the downward position by the reset magnet 56. The coil spring I48, however, rotates the lever arm I38 counter-clockwise about its pivot I44 and causes the valve .40 to be disengaged from its seat against the bias of the spring 42.

. It is apparent that if the push rod I24 is being .forced downw'ardly by thelclock actuator during the resetting operation, then the collar II2 on the thrust button 12 will be unable to engage the bearing surface II52 on lever arm I38 until the downward movement of the thrust button is nearly completed. Similarly, the coil spring I48 can bias the lever arm I38 only up to the point wsen. the lever arm is stopped bythepush rod I24. The remainder of the movement will occur when the clock actuator releases pressure on the push rod I24-causing retraction ofthis'member.

From the foregoing description of th improved controldevice, it becomes apparentthat primary and secondary means maybe employedvfor operating a valve or other control means. Thus, the primary meansmay be the thermomagnetic unit and the secondary means a clock timer as preferred herein. Whileit is desirable for the valve to be under safety control of the thermomagnetic unit at all times, it is apparent that the clock timer could be additional equipment to be installed when desired. Provision has been made for the addition of the clock control whenever desired and for its removal for repair without interruptionof range operation. under full safety control.

, It is understood that many changes may be madein the combination and arrangement of parts and in the details of construction within the scope of the appended claims without departing from the spirit of the invention.

I claim:

1; In a controldevice, control means movable between open and closed positions and biased to said closed position,- a first pivotally mounted lover, a second lever pivotally mounted on said first lever and being engageable with said control means, actuating means cooperable With said second lever for moving said second lever into operative relation with said control means and overcoming the bias of said control means and causing movement of said control means to open position, positioning means operatively engageable with said first lever for positioning said second lever to render said actuating means efiective or ineffective to overcome said bias according to the presence or absence respectively of a controlling condition, and means for rotatingsaid second lever on said first lever to move said sec,- ond lever out of operative relation with said control means to thereby render said actuating means ineffective to overcome said bias during the presence of said condition.

2. In a control device, control means movable between open and closed positions and biased to said closed position, a first pivotally mounted lever, a second lever pivotally mounted on said first lever and being engageable with said control means, yieldable means cooperable with said second lever for overcoming the bias of said control means and causing movement of said control means to open position when said second lever is in operative engagement With said control means, electromagnetic means operatively engageable with said first lever for positioning said second lever to render said yieldable means effective or ineiIective to overcome said bias according to the energized or deenergized condition of said electromagnetic means, means for establishing an engaged relation between said first, lever and said electromagnetic means including a movable element slidable relative to said electromagnetic means and being engageable with both said levers to move said first lever into engagement with said electromagnetic means while retaining said second lever out of operative relation with said control means and said yieldable means inoperable for overcoming the bias of said control means, said first lever being retained in engagement with said electromagnetic means while said second lever is rotated in one direction by said yieldable means if said electromagnetic means is energized when saidmovable element is released, and means for rotating said second lever in the opposite direction on said first lever to cause said control means to be closed under its bias in the energized condition of said electromagnetic means.

3. In a control device, the co bination of control means movable between co trolling positions and being biased to one of said positions, a lever device positioned to be operatively engageable with said control means, yieldable means cooper-.- able with said lever device for positioning the same in operative relation with said control means for overcoming the bias of said control means and causing movement thereof to another of said positions, positioning means operatively engageable with said lever device for positioning said lever device to render said yieldable means operable for overcoming the bias of said control means only during the existence of a controlling condition and inoperable for overcoming said bias in the absence of said condition, and means operable on said lever device for overcoming said yieldable means and causing movement of said control means under said bias to said one position.

4. In a control device, the combination of control means movable between controlling positions and being biased to one of said positions, a lever device adapted to be positioned for operative engagement with said control means, yieldable means cooperable with said lever device for overwhen said lever device is positioned inoperative engagement with said control means, holding means cooperable with said lever device having a first position during the existence of a controlling condition in which the leverdeviceis positioned in operative engagement with the control device and a second position in the absence of said condition in which thelever device is positioned out of operative engagement with said control device, means operable on said lever device'for overcoming said yieldable means and causing movement of said control means under said bias to said one position, and means for setting said-holding means in said first position upon establishment of said condition while rendering said lever device and said yieldable means inoperable for overcoming the bias, of said control means. 1

5, In a control device. the combination of con- A trol means movable between controlling positions and being biased to one of said positions, a lever device having relatively fixed and movable pivots and adapted to be positioned for operative engagement with said control means, said lever device being so constructed and arranged that rotation thereof on said fixed pivot will cause movement of said movable pivot, yieldable means adapted to rotate said lever device in one direction on said movable pivot for overcoming the bias of said control means when said movable pivot is in a first position and said lever device is in operative engagement with said control means, means operable on said lever device for overcoming said yieldable means and causing rotation of said lever device in another direction on said movable pivot V and movement of said control means undersaid bias, holding means operatively associatedwith said lever device for retaining said movable pivot insaid first position during the existence of a controlling condition, means for rotating said lever device on said fixed pivot and causingmovement of said movable pivot to a second position in the absence of said condition, said lever device and said yieldable means being inoperable for overcoming the. bias of said control means when device comprising a pair of lever arms, one of said lever arms having a relatively fixed pivot and the other of said lever arms being adapted for operative engagement with said control means and having a pivot movable with said one lever arm, yieldable means adapted to rotate said other lever arm in one direction on said movable pivot for establishing an operative relation between said other lever arm and said control means and overcoming the bias of said control means while said movable pivot is in a first position, holding Vmeans operatively engageable with said one arm for retaining said movable pivot in said first position during the existence of a controlling condition, means operatively engageable with said other arm for overcoming said yieldable means and causing rotation of said other lever arm in another direction on said movable pivot and movement of said control means under said'bias, and means for rotating said one arm on said fixed pivot and causing movement of said movable pivot to a second position in the absence of said condition, said other arm and yieldable means being inoperable for overcoming the bias of said control means while said movable pivot is in said second position.

7. In a control device, the combination of trol means movable between controllingpositions and being biased to one of saidpositions, a lever device comprising a pair of lever arms, one of said lever arms having a relatively fixed pivot and. the other of said lever arms having a pivot movable with said one lever arm and adapted for operative engagement with said control means, yieldable means adapted to rotate said other leverarm: in one direction on said movable pivotinto operative engagement with said control means for overcoming the bias of said control meanswhileisaid movable pivot is in a first position, holding) nfeans operatively engageable with said one armfor retaining said movable pivot in said first position during the existence of a controllmg'condition, means operatively engageable with said other rm for overcoming said 'yieldable 'meansand causing rotation of said 'otherlever' arm in another direction on said movable l pivot andfmove ment of said control means under 'saidib' means forrotating said onearmj onsaid fixed pivot and causing movement of said movable pivot to a second position in the abse'n'ceflof saidicondition, said other arm e and yieldable meansfbeing out of operative relation with 's'a'idicontrol means and being thereby inoperabl'e for overcoming the bias of said control means whensaid movable pivot is in said second'p'osition, andfsettifn'g' means for establishing an operative relation between said lever device and' said holding means, while retaining said otherilever arm and yieldable means inoperable for overcoming the bias of said control means, said setting means including a movable element operatively engageable with both said lever arms for rotating said other lever .arm in said other direction on said movable pivot and for rotating said one lever arm on said fixed pivot and causing movement of said movable pivot to said first position.

8. In a control device, the combination of control means movable between controlling positions and being biased to one of said positions, a lever device comprising a pair of lever arms, one of said lever arms having a relatively fixed pivot at one end thereof and the other of saidlever arms having a pivot intermediate its ends and being adapted for operative engagement at one end with said control means, said last named pivot being carried by said one lever arm and movable therewith upon rotation of said one lever arm on said fixed pivot, yieldable means engaging the opposite end of said other lever arm for rotating the same in one direction on said movable pivot into operative engagement with said control means for overcoming the bias of said movable means while said movable pivot is in a first position, holding means operatively engageable with the opposite end of said one lever arm for retaining said movable pivot in said first position during the existence of a controlling condition, means operatively engageable with said other lever arm between said movable pivot and said yieldable means for overcoming the latter and causing rotation ofsaid other lever said condition; said other lever arm and yieldable means being out'of operative engagement with said control means and being thereby inoperable for'overcoming the bias of said control means while said-movable pivot is insaid second position, andsetting means for establishing an opeif'ative relationbetween'said lever device and said holding" means while retaining said other levenarm and yieldable means inoperable for overcomingthejbias of said control means, said setting" means including a movable element operatively engageable with both said leverarms forrotatin'g 'said other lever arm in said other direction on said movable pivot and for rotating saidone lever arm on said fixed pivot and causin'g movement of said movable pivot to said first position; v V

9I'In'a'control device, the combination of 'a casing, control means in said casing movable between controlling positions and biased to one of said positions, a lever device adapted to be positioned'for operative engagement with said control means, yieldable means cooperable with said lever device for overcoming the bias of said control means and causing movement thereof to another of said positions while said lever device is positioned for operative engagement with said control means, means visible exteriorly of said ingsaid lever device out of operative relation with said control means to render said lever device'inoperable for overcoming said bias in the absence of said condition.

l0In acontrol device, the combination of a casing, control means in said casing movable between controlling positions and being biased to one of saidpositions, a lever device adapted to be positioned for operative engagement with said control means, yieldable means cooperable with said lever device for overcoming the bias of said control means and causing movement thereof to another of said positions when said lever device is in operative engagement with said control means, means visible exteriorly of said casing for indicatingthe positionof said lever device, actuating means movable with said lever device and projecting'exteriorly of said casing, connecting means extending between said indicating means and said actuating means, and means for positioning said lever device in operative relation with said control means to render said leverdevice and said yieldable means operable for overcoming the bias of said control means during the existence of a controlling condition and for positioning said lever device out of operative relation with said control means to render said lever'device inoperable 'for overcoming said bias in the absence of said condition HAROLD RICE.

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